Elevator for quick assemblage and use in limited access enclosures



ELEVATOR FOR QUICK ASSEMBLAGE AND USE IN Jan. 7, 1969 TEXT-OR 3,420,332

LIMITED ACCESS ENCLOSURES Filed July 14, 1967 Sheet of 2 -Fi 9.1. 55 is /4 5 2 m Fig.2 i a 4 .32 z {9 v 76 72 I I 7/ n l E /6 95 I v 32 L .1 I a i 3 26g? 26 16 Y \f 57 72 71 10 Q 26 54 INVENTOR.

ATTORNEY ATTORNEY Sheet 7, 1969 R. A. TEXTOR ELEVATOR FOR QUICK ASSEMBLAGE AND USE IN LIMITED ACCESS ENCLOSURES Filed July 14, 1967 United States Patent 6 17 Claims ABSTRACT OF THE DISCLOSURE A quickly assembled and disassembled elevator for dairy silos and other limited access enclosures comprising a plurality of detachably coupled parts providing a lift platform with power unit, guide and drive sprockets for four lift support chains, and protective railing means for said platform, a plurality of other detachably coupled parts providing an elongated suspension unit rotatable on a tubular suspension shaft, having means for mounting at the top of an enclosure, spaced transverse chain anchoring members offset in one direction with respect to said suspension shaft and a counterbalance offset in the opposite direction, having roller engagement with the enclosure top when the suspension unit is raised, with chains attached, to the top of the enclosure, and a movable control station for said power unit permitting raising and lowering of the assembled lift platform selectively from the base of the enclosure and from the lift platform.

Background of the invention In limited access, vertically extended enclosures such as the milk storage tanks or silos used in the dairy industry, it has heretofore been extremely difficult to properly inspect and maintain the interior of such enclosures. Dairy silos, for example, may be to 12 feet in diameter and 30 to 60 feet high and are normally equipped, in a lower side wall, with an access manhole providing at most a 22 to 24 inch opening. Such silos are generally lined with stainless steel, glass, or other highly resistant material, so that these surfaces can generally be effectively cleaned with proper solutions dispensed by mechanical sprayers which can be raised and lowered within the silo through a central access tube or pipe fitting at the top.

It is possible, even with the most resistant construction materials and careful cleaning techniques, for deposits to accumulate which can harbor bacteria or otherwise contaminate milk stored in such silos, and it is important, from time to time, to make full inspections of the silo interior using ultraviolet light and other inspection aids. Heretofore this has been accomplished by erecting scaffolding within the silo from bits and pieces small enough to be passed through the manhole, a procedure which is extremely costly and time consuming.

The invention The problems above described are overcome in accordance with the present invention by providing an elevator device comprising a suspension unit and a lift platform, each made up of a plurality of easily assembled and disassembled parts, with these parts as disassembled being readily passed through an access manhole having a maximum dimension of 22 to 24 inches. The elevator, which can be completely assembled and ready to operate within a to minute period, provides freedom of movement vertically and circumferentially as desired by the operator so that all inner surfaces of dairy silos and other vertical cylindrical enclosures can be closely examined and reached for cleaning and repair.

The versatility of the new elevator device is provided by the overall combination of elements and the structural details of the 'multi-component suspension unit and the multi-component lift platform thereof. The suspension unit comprises a main frame having a bearing portion which receives a tubular suspension shaft with short and long arms projecting in diametrically opposite directions from said bearing portion; a pair of detachable transverse yoke members secured to said frame, one at the protruding end of said long arm and the other at the inner end of said short arm, and each having notched ends for receiving lift supporting chains, and a counterbrace detachably secured at the end of said short arm and extending transversely of said frame, with end rollers adapted for rolling engagement with the top of an enclosure.

The left platform comprises a plurality of platform sections with one carrying a power unit and two others carrying chain guide and drive sprockets with interfitting means on the power unit and drive sprockets to engage the same as the platform sections are secured in juxtaposed position. The platform sections are joined by brace members, coextensive with the assemblage which also provide means for mounting components of a protective railing structure. Control of the power unit is effected from a control station at the end of a long flexible conductor permitting the control to move with the lift platform or to remain, and be operate-d from, the base of the enclosure. The platform is preferably divided lengthwise to a center section with the power unit and two similar (mirror image) side sections with the side sectons including side bins for storage of the suspension chains when the elevator is disassembled.

The power unit comprises a conventional electric motor with dual starters to permit operation in both directions, and the motor is coupled directly with a gear reducer, the output shafts of which carry the coupling means which interfit with the drive sprockets. Except for this quick coupling feature and the movable control station the details of the power unit can be found in a variety of commercially available equipment, and provide no part of the present invention.

For a more complete understanding of the quickly assemblable elevator and the suspension unit and lift platform thereof, the following description should be considered with reference to the accompanying drawing in which a preferred adaptation of the invention is illustrated with the various parts thereof identified by suitable reference characters in each of the views, and in which:

FIG. 1 is a sectional view through a dairy silo showing the elevator assembled therein.

FIG. 2 is a view looking in the direction of the arrows 22 in FIG. 1.

FIG. 3 is a sectional view of the suspension structure substantially on the line 33 of FIG. 1.

FIG. 4 is an enlarged side view of the suspension unit as shown in FIG. 1.

FIG. 5 is a side view of a chain hanger substantially on the line 5-5 of FIG. 4.

FIG. 6 is a top view of the counterbrace as viewed in the direction of the arrows 66 in FIG. 4.

FIG. 7 is an enlarged partial plan view of the lift platform as seen in FIGS. 1 and 2.

FIG. 8 is a sectional view of the lift platform substantially on the line 88 of FIG. 7, and

FIG. 9 is an enlarged exploded view, substantially on the line 99 of FIG. 7 illustrating the interengagement of power unit and drive sprockets.

In FIGS. 1 and 2 of the drawing there is shown the outline of a dairy silo 10 having sidewalls 11 with an access manhole 12 at the lower portion thereof, and a top wall 13 with a central tubular extension or pipe fitting 14 (shown in larger detail in FIG. 3). At the top of the silo is a suspension unit 15 connected by chains 16 to a lift platform 17 which moves up and down the chains, and

which together with the suspension unit rotates within the silo as indicated by the arrows 18 in FIG. 2. The components of the suspension unit 15, which are more fully illustrated in FIGS. 3 to 6, and the components of the lift platform 17 which are more fully illustrated in FIGS. 7 to 9 are all small enough to be passed through the manhole 12 for quick assembly within the silo.

The suspension unit comprises a main frame 18 made up of a vertical shaft 19 terminating in an upper bearing 20 and lower bearing 21, as clearly shown in FIGS. 3 and 4, from which extend in diametrically opposed positions a long arm 22 and a short arm 23 in alignment with the bearing 21 and angularly disposed members 24 and 25 joining remote ends of said arms with the bearing 20. These parts are suitably welded together and supplemental stiffening means 26 may join the angular members 24 and 25.

Detachably secured to the frame 18 are a pair of transverse yoke members 26, 26 of similar structure having end notches 27 for receiving the chains 16, but with the spacing of the notches 27 differing slightly to correspond with the chain sprocket spacing on the platform 17, as hereinafter described. The yokes 26, 26 have perpendicularly disposed and closely spaced flanges 28, 28', the flanges having aligned apertures 29, 29' for bolting the yokes to the frame 18 through appropriate apertures 30 and 31 which are located respectively at the free end of the long arm 22 and at the inner end of the short arm 23. Also secured to the frame 18 at the end of the short arm 23 is a counterbrace 32 comprising an upstanding member 33 having a forked lower end 34 for bolting to the frame 18, and a transverse arcuate yoke 35 at the upper end thereof having forked ends 36 receiving rollers 37 which bear against the inner surface of the upper wall 13 of an enclosure as seen in FIG. 1.

The frame 18 is carried by a tubular suspension shaft 38 having an outwardly protruding flange 39 at the lower end thereof for engaging the bearing 21 and having a threaded portion 40 protruding substantially beyond the bearing 20 to extend through the tubular extension 14 in the enclosure top 13 as seen in FIG. 3. The threaded portion 40 receives a suitable nut 41 and washer 42 which bears against the upper end of the tubular extension 14 to anchor the suspension unit 15 at the top of the enclosure to permit its free rotation around the suspension shaft 38. Raising and lowering of the suspension unit 15 with the chains 16 attached thereto is effected by means of a rope or cable 43 passing through the tubular extension 14 and the tubular suspension shaft 38 and knotted or otherwise anchored at the lower end of the suspension shaft as indicated at 44.

The lift platform 17 is made up of a central channel section 45 and two narrower channel sections 46, 46 which are quickly bolted together by transverse angle irons or braces 47. These braces 47 also support by bolts or other detachable fasteners 48 upstanding U-frames 49 forming end guard rails on the platform which may be joined, if desired, by detachable side rails 50.

Within the central channel part 45 adjacent to one end thereof is mounted a motor 51 and reduction gear unit 52 with drive shafts 53 at opposed sides thereof terminating in bayonet groove coupling members 54 aligned with apertures 55 in the legs of the channel member 45 as clearly shown in FIG. 9.

The side channel members 46, 46' are in every respect mirror images of each other having through a major portion of their length invertedchannel portions 56, 56' protruding outwardly therefrom and providing chain storage bins. Each of the side channel members carry a dual drive sprocket 57 mounted on a shaft 58 supported in suitable bearings 59 with the shaft protruding through an aperture 60 in the inner channel wall so that laterally protruding lugs 61 on the shaft 58 can engage the bayonet coupling 54 as the side channel member 46 or 46' is brought into abutting engagement with the central channel member 45. Thus it will be apparent that a positive drive of the sprockets 57 is assured when the platform sections have been joined by the braces 47.

In addition to the drive sprockets 57 each of the side sections 46, 46' carry a dual idler sprocket 62 in closely spaced relation to the sprocket 57 and a single idler sprocket 63 at the opposed end of the platform section. A smaller single idler sprocket 64 is arranged adjacent to sprocket 57 and between this and sprocket 63 with the axis of the sprocket 64 being above the axis of the other sprockets as seen in FIG. 1. The idler sprockets are carried on shafts mounted in suitable bearings 62, 63 and 64' within the channel members 46, 46.

The suspension chains 16 secured to the yoke 26 pass under sprockets 63 over sprocket 64, under the drive sprockets 57 and over sprocket 62; while the chains secured to yoke 26 pass under sprockets 62 and over drive sprockets 57 as indicated in FIG. 1 of the drawing. Thus, as viewed in FIG. 1, a clockwise rotation of the drive sprockets 57 causes upward movement of the lift platform 17 on the chains 16, and a counterclockwise movement of the drive sprockets 57 causes downward movement of the lift platform. The chains should engage teeth of the sprockets 57 through at least of the circumference thereof; and if desired, conventional guards (not shown in the drawing) can be employed to prevent possible accidental displacement of the chains from the drive sprockets.

As earlier mentioned, the motor 51 has dual starters for reverse operation and is preferably provided with a movable control station 65 at the end of a long flexible conductor 66 and having a control button 67 to initiate lifting movement, a control button 68 to initiate lowering movement and a control button 69 for stopping the motor 51. The control station 65 can thus be operated by a person remaining at the base of the enclosure or can be carried by the lift platform suitably positioned on the guardrail 49 by a hook 70.

The chains 16 are quite flexible in one plane permitting free rotation around the idler and drive sprockets but are relatively stiff in a plane perpendicular thereto. There is little tendency for the platform 17 to swing from side to side, but there is a tendency for swinging motion toward and from the enclosure unit 11, particularly when the platform 17 is suspended a substantial distance below the suspension unit 15. It is desirable, therefore, to provide stabilizing and enclosure protecting rollers 71, suitably made of rubber or other resilient material at the corners of the platform which are nearest the Wall 11. These rollers can be mounted in various ways but are suitably mounted, at an angle of about 45 to the platform edge, by means of brackets 72 which may be joined to the assemblage by the same bolts or fasteners used to secure the brace 47 to the platform section 46, 46', as shown in FIG. 7 of the drawing.

For best performance in checking swinging movement of the platform the brackets 72 should be of a size to positively engage the rollers 71 with the wall 11 and cause a slight defection of the chains 16 from the vertical or free hanging position. In this way a small component of force holds the platform against the wall 11, but a person riding the elevator can easily push against the wall 11 to disengage the rollers 71 from the wall 11 when rotary movement of the lift platform 17 within the enclosure is desired.

The procedure in assembling the elevator mechanism within the silo 10 can be briefly described as follows:

The center section 45 and the side sections 46, 46 with the chains 16 stored in the bins 56, 56' are individually passed through the manhole 12 and secured together by means of the angle iron braces 47. The suspension unit 15, either assembled or wholly or partially disassembled, is then passed through the manhole 12 and placed on the lift platform. The extent to which the suspension unit can be preassembled externally of the silo will of course depend upon the size of the manhole. Generally it is possible to attach the yoke 26 and the counterbrace 32 before passing the assemblage through the manhole, leaving only attachment of the yoke 26' to be completed within the enclosure.

A rope or cable 43 is then lowered from the top of the enclosure and secured to the tubular suspension shaft 38, as previously described. The chains 16 are then hooked in the appropriate notches 27 of the yokes 26, 26 and the suspension unit with the chains attached is raised to the top of the enclosure and anchored in the manner previously described. When this operation is completed the end railings 49 and the side railings 50', if desired, are secured to the lift platform and the elevator is ready for operation.

Assembling the elevator in the manner above described, or disassembling the mechanism by the reverse sequence of steps can readily be accomplished within a period of to minutes. Workmen using the elevator can then quickly reach any inner surface of the enclosure by raising or lowering the lift platform 17 or by manually rotating the suspension unit together with the chains and lift platform within the enclosure. The desired proximity of the workmen to the enclosure walls may vary depending upon the nature of the inspection, cleaning, or other servicing to be accomplished. To this end there are preferably a plurality of apertures 30 and 31 permitting the yokes 26, 26' to be appropriately positioned longitudinally of the frame 18. This selective positioning of the yokes 26, 26' can also serve to accommodate the elevator mechanism for use in silos or enclosures of differing diameter. Thus for example, a particular size frame 18 might be suitable for use in silos having a diameter as small as 10 feet or as large as 12 feet. This varying in the positioning of the load is effectively compensated for by the counterbrace 32 and its rolling engagement with the inner surface of the top wall 13 of the enclosure.

The foregoing description emphasizes the manner in which the suspension unit and lift platform complement each other in providing a versatile, yet quickly assembled and disassembled unit for gaining free access to interior surfaces in vertically extended confined spaces. Particular mention has been made of dairy silos since there is a special need for more effective means for inspecting, cleaning, and maintaining such silos.

It is to be understood, however, that the suspension unit and the lift platform are each considered to have novel structural features, and to have independent utility. By way of illustration, the lift platform can be used in connection with any fixed or movable suspending means which provides appropriate spacing of the lift support chains. Thus the lift platform could be effectively used in connection with any interior or exterior vertical surface, with the novel structure and easy assemblage greatly facilitating the moving of the platform from place to place, and the storage of the platform when not in use.

Similarly, the suspension unit can be used to support any lift device which must maintain a load in a position laterally offset with respect to an available point of suspension. The important basic structure of the suspension unit is the load supporting arm 22 protruding from the mounting shaft or bearing 19 in a direction diametrically opposed to the counterbrace carried by the arm 23. A lift device could readily be suspended from a single yoke member 26, or directly from the protruding end of the arm 22. By way of illustration, a simple block and tackle, with the upper pulley hooked in one of the apertures 30 and the lower pulley attached to a chair sling, Would permit a workman to reach all vertical surfaces of a silo or similar structure.

Various changes and modifications in the suspension unit, lift platform, and complete elevator apparatus as herein disclosed may occur to those skilled in the art and to the extent that such changes and modifications are embraced by the appended claims it is to be understood that they constitute part of the present invention.

Iclaim:

1. A quickly assembled and disassembled elevator for dairy silos and other limited access enclosures comprising a plurality of detachably coupled parts providing a lift platform with power unit, and guide and drive sprockets for lift support chains, a plurality of other detachably coupled parts providing an elongated suspension unit rotatable on a tubular suspension shaft having means for mounting at the top of an enclosure, spaced transverse chain anchoring members offset in one direction with respect to said suspension shaft and a counterbrace offset in the opposite direction having roller engagement with an enclosure top when the suspension unit is raised, with chains attached, to the top of the enclosure, and control means for actuating said power unit to selectively raise and lower the lift platform on said chains.

2. An elevator as defined in claim 1, wherein additional detachably coupled parts provide a guard railing for said lift platform.

3. An elevator as defined in claim 1, wherein additional detachably coupled parts provide bearing rollers at one end of the lift platform adapted to bear against the enclosure wall when the lift platform is suspended by said chains.

4. An elevator as defined in claim 1, wherein additional detachably coupled parts provide bearing rollers at one end of the lift platform adapted to bear against the enclosure wall when the lift platform is suspended by said chains, said rollers being oriented to rotate in the raising and lowering of said lift platform, and the rollers being readily disengageable from the enclosure wall to permit rotation of the suspension unit and lift platform within the enclosure.

5. An elevator as defined in claim 1, wherein the control means is a movable control station on an elongated flexible conductor permitting the same to be selectively operated from the base of the enclosure and carried by said lift platform.

6. An elevator as defined in claim 1, wherein means is provided for varying the position of said chain anchoring members longitudinally of said suspension unit.

7. An elevator as defined in claim 1, wherein the detachably coupled parts of said lift platform include a central channeled member housing said power unit with drive shafts exposed at opposed sides of said channeled member, and two similar, mirror image, side channeled members adapted for support in juxtaposition with said central channel member by transverse connecting braces, said side channel members carrying said guide and drive sprockets, and inter fitting means on the shafts of said drive sprockets and drive shafts of said power unit permitting automatic engagement therebetween as the channeled members are moved to juxtaposition.

8. A suspension uni-t for rotatable mounting at the top of an enclosure, said suspension unit comprising a main frame having a vertical tubular bearing with horizontal long and short arms projecting in diametrically opposed directions from said bearing, a suspension shaft extending through said bearing and having means at the upper end thereof for positioning the same within an enclosure, load supporting means at the free end portlon of said long arm, and a counterbrace at the free end portion of said short arm carrying spaced rollers for engagement with the inner surface of the enclosure 9. A suspension unit as defined in claim 8 wherein said load supporting means comprises a yoke disposed perpendicularly to said long arm having load positioning means equally spaced from said arm.

10. A suspension unit as defined in claim 8 wherein said load supporting means comprises a yoke disposed perpendicularly to said long arm having load positioning means equally spaced from said arm, and a second yoke parallel to said first named yoke secured to said frame in close proximity to said bearing.

11. A suspension unit as defined in claim 10, wherein said suspension shaft, yoke members and counterbrace are separate parts readily attachable and detachable with respect to said main frame.

12. A suspension unit as defined in claim 11, wherein the detachable mounting of said yoke members includes means for varying the position of said yoke members longitudinally of said frame.

13. A suspension unit as defined in claim 8 wherein said suspension shaft is of tubular structure facilitating the raising and lowering of said suspension unit by strand means passing through said tubular shaft.

14. A lift platform adapted for quick assembly and disassembly comprising a central channeled member carrying a power unit with drive shafts exposed at opposed sides thereof, a pair of similar, mirror images, side channeled members carrying guide and drive sprockets for lift support chains, detachable transverse brace members for securing said side channeled members in juxtaposition to said central channeled member, and interfitting means on the shafts of said drive sprockets and the drive shafts of said power unit permitting automatic engagement therebetween as the channeled members are moved to juxtaposition.

15. A lift platform as defined in claim 14, wherein said transverse brace members also detachably support a guard rail for said lift platform.

16. A lift platform as defined in claim 14, wherein said side channeled members include, at the sides thereof remote from said central member, inverted channel portions forming storage bins for said lift support chains.

17. A lift platform as defined in claim 14, wherein each of said side channeled members have a double guide sprocket at one end thereof, a double drive sprocket closely spaced therefrom, a single guide sprocket at the other end thereof, all with axes in a common plane, and a smaller single idler sprocket between said single guide sprocket and drive sprocket, having its axis upwardly spaced from said common plane, one chain passing under the single drive sprocket, over the idler sprocket, under the drive sprocket and over the double guide sprocket, and another chain passing under the double guide sprocket and over the drive sprocket.

References Cited UNITED STATES PATENTS 1,090,856 3/1914 Johnson 182128 2,972,394 2/1961 Grant l82l44 3,183,997 5/1965 Kleiss 182-128 3,306,396 2/1967 Goss 182l28 REINALDO P. MACHADO, Primary Examiner.

US. Cl. X.R. 182144, 

